Morphological and taxonomic studies on mammalian trypanosomes. II. Trypanosoma simiae and acute porcine trypanosomiasis in tropical Africa

Abstract

This paper deals with the aetiology of an acute form of trypanosomiasis among pigs in tropical Africa. The study of the parasites from a number of cases showed that they all represent a polymorphic trypanosome of the same type. Are-examination of Bruce's original Trypanosoma simiae revealed in it a similar polymorphism and established its identity with the trypanosome responsible for the outbreaks among pigs. A revised description of T. simiae (summarized in the Diagnosis on p. 642), is given and its systematic position is discussed. It is shown that T. simiae has affinities both with members of the congolense-group and with those of the brucei-group, and should occupy an intermediate position. The division and auto-agglutination in this trypanosome are described for the first time. An account is given of all the known instances of acute pig-trypanosomiasis. While in some of these it was possible to demonstrate the presence of T. simiae by examination of films, in others the presence of this trypanosome could be inferred from a critical analysis of the records. The epidemiological data concerning these outbreaks are also briefly discussed.